Weed cutter for outboard motors



.w I I Oct. 5, 1954 H. F. CAVANAUGH WEED CUTTER FOR OUTBOARD MOTORSFiled June 26, 1951 Patented Oct. 5, 1954 UNITED STATES PATENT OFFICE 3Claims.

This invention relates to outboard motors and more particularly to meansfor cutting weeds in the path of such motors and for improving thesteering characteristics thereof.

Many devices are known in the prior art designed to prevent theentanglement of weeds with the motor propeller, but such devices havefailed in their purpose with the result that the weeds wind around thepropeller shaft, resulting in poor motor operation or stopping of themotor. Such prior art cutter devices as have been designed to cut theweeds have not been practical, inasmuch as they merely cut the weeds inline with the propeller drive shaft, thereby permitting weeds at thesides of the cutter to become entangled with the propeller. Furthermore,most prior art devices of this type have impaired the steeringcharacteristics of the motor.

Accordingly, a primary object of the present invention is to cut theweeds, not only in line with the propeller drive shaft, but also invertical planes between which the rotational path of the propeller isentirely disposed, to positively prevent the tips of the propellerblades from becoming entangled with the weeds.

A further object of the invention is to devise a cutter device, such asabove described, which may be quickly and easily connected to standardoutboard motors and which can be adjusted so that the lower ends of thecutters are below the 1ower level of the propeller blades duringrotation thereof.

Still another object of the invention is to devise an arrangement inwhich the cutter may be tilted to increase its cutting efiiciency andmay be adjusted fore and aft with respect to the propeller.

A more specific object of the invention is to devise a cutter devicewherein at least three parallel blades are provided, one in alignmentwith the propeller drive shaft, and the others in planes within whichthe propeller is entirely disposed during rotation thereof.

Yet another object of the invention is to provide means for adjustingthe cutter blades relative to each other to increase or decrease thespace between the cutting edges thereof by relative fore and aftmovement of the blades.

A further object of the invention is to improve the steeringcharacteristics of the motor by providing one or more weed cutters, eachin the form of a flat knife-like blade, disposed in a plane parallel orcoplanar with the rudder, to function as secondary rudder means inunison therewith.

The foregoing and other objects and advantages of the invention willbecome apparent from aconsideration of the following specification andthe accompanying drawings, wherein Fig. 1 is a perspective view of aconventional outboard motor with a preferred embodiment of the novelcutter device attached thereto;

Fig. 2 is a front elevational view of the novel cutter device shown inFig. 1;

Fig. 3 is a side elevational view of the cutter device; and

Fig. 4 is a top plan view thereof.

Describing the invention in detail and referring first to Fig. 1, aconventional outboard motor, generally designated 2, comprises a driveshaft housing 4 extending substantially vertically from the under sideof a motor casing 6, the lower end of the housing 4 terminating in aconventional gear box 8 containing gear means (not shown) connecting thedrive shaft (not shown) within the housing 4 to a propeller I0. Aconventional rudder 12 disposed in a substantially vertical plane, isformed on the under side of the gear box 8. The housing 4 is mounted inthe usual manner on a boat clamp l3 for rotation relative thereto on asubstantially vertical axis to steer the boat.

The novel cutter device, generally designated I4, which may be made ofstainless steel or any other desired material, is connected to thehousing 4 by means of a pair of clamp straps I 6, arcuately formed toconform to the shape of the housing 4 and interconnected by a bolt andnut assembly 8 to clamp the straps [6 around the housing 4 undersufficient tension to hold the device l4 tightly in position thereon.The device I4 is also supported by one or a pair of pivot links 29,pivotally connected to the rudder 12 by a bolt and nut assembly 22passing through the links 20 and the rudder I2.

As best seen in Figs. 2 and 4, the cutter device l4 comprises a centralblade 24, which is in the form of a thin fiat plate having a cuttingedge on its forward surface, as at 26, said edge having rearwardlydiverging segments 28 and 30, as best seen in Fig. 3. These divergingsegments greatly increase the cutting efficiency of the blade as itpasses through vegetation in the water, inasmuch as the divergence ofthe segments 28 and 30 produces a slicing action, severing weeds againstwhich the blade is forced by the motor 2. The blade 24 is preferablyconnected to the straps 16 by a bolt and nut assembly 32 passing throughan aperture 34 in the blade 24, and said aperture is preferablyvertically elongated, as best seen in Fig. 3, to accommodate verticaladjustment of the blade 24 to a position whereat its lower extremity isbelow the lower level of the rotational path of the propeller l0,whereby weeds are prevented from passing beneath the blade 24 intoengagement with the propeller.

Also, as best seen in Fig. 3, the pivot links 20 are connected to theblade 24 by a bolt and nut assembly 36 which extends through acomplementary aperture of the blade 24 and through an elongated arcuateslot or aperture in each link 20 to accommodate tilting of the blade 24by rotation thereof on a substantially horizontal axis about the boltand nut assembly 34. It may be noted in this connection, that by thustilting the blade 24, its cutting efiiciency may be increased, by reasonof the slicing action imparted to the blade.

The cutter device [4 also preferably comprises a pair of spaced,relatively short, fiat blades 40 and 42 disposed in planes substantiallyparallel to the plane of the blade 24 and having cutting edges 44 and 46on the forwardly facing edges thereof, said edges having slopingsegments 41 parallel to the segment 30 of the cutting edge 26. The upperends of the blades 40 and 42 are flanged, as at 48 and 55 respectively,the flanges being provided with bolt and nut assemblies 5| and 52extending through complementary openings thereof and also extendingthrough horizontally elongated slots 54 and 56 of straps or brackets 53and 56 secured to opposite sides of the blade 24, as for example, bybolt and nut assemblies 82 or by any other desired securing means, suchas rivets or welds.

As best seen in Fig. l, the upper edges of the blades 45 and 42 extendabove the upper level of the rotational path of the propeller l0, andthe lower ends of these blades preferably extend below the lower levelof the rotational path of the propeller. Furthermore, the blades 40 and42, which, as above noted, are in planes parallel to that of the blade24, are preferably so arranged that the rotational path of the propellerI is entirely disposed between the planes of the blades 40 and 42,thereby preventing the tips of the propeller blades from extendinglaterally beyond the blades 45 and 42 and encountering uncut weedspassing therealong.

Another feature of the invention resides in the manner in which thespace between the cutting edges of the blades 45 and 42 and the cuttingedge of the blade 24 may be increased or decreased by adjustment of theblades 40 and 42 in a fore and aft direction with respect to the blade24. This is accomplished by loosening the bolt and nut assemblies and 52and moving the blades 48 and 42 lengthwise of the slots 54 and 56 untilthe desired spacing between the cutting edges of the blades is obtained,whereupon the bolt and nut assemblies 5| and 52 may be tightened. Itwill be understood that when the outboard motor 2 is operated in waterscontaining different types of vegetation, different spacing between thecutting edges 44, 46 and 26 may be desired.

It may also be noted, as best seen in Fig. 1, that the blade 24 ispreferably coplanar with the rudder I 2, and the blades 40 and 42 are inplanes parallel with respect to that of the rudder l2. Furthermore, allof the blades are preferably in the form of very thin, substantiallyflat, straps resembling knife blades, to afford minimum resistanceagainst the water when the boat driven by the motor 2 is steered in astraight line. Also, the configuration of these blades is such thatextreme sensitivity of steering is achieved, and their form andarrangement accommodates their function as auxiliary rudder means.

In this connection, it may be noted that the brackets 58 and 60 alsoafford minimum resistance to flow of water therearound, inasmuch as isbest seen in Fig. 2, these parts are preferably in the form of thin fiatstraps which may, if desired, be formed with cutting edges similar tothose of the blades 24, 40 and 42.

The brackets 58 and 60 may be elongated if desired to accommodateadditional blades and five or seven or any number of blades may be usedas desired and as may be required in waters with heavy vegetation.

It is apparent that the specific illustrations shown above have beengiven by way of illustration and not by way of limitation and that thestructures above described are subject to variation and modificationwithout departing from the scope or intent of the invention, all ofwhich variations and modifications are to be included within the scopeof the present invention.

What is claimed as new and desired to be secured by Letters Patent is asfollows:

1. A weed cutter device for an outboard motor comprising a substantiallyflat, vertical blade having a forwardly facing cutting edge, a pair ofsubstantially fiat bracket straps secured to opposite sides of saidblade and projecting rearwardly therefrom, a pair of substantially fiatvertical blades having forwardly facing cutting edges, means adjustablysecuring said pair of blades to the respective bracket straps foradjustment fore and aft with respect to the first-mentioned blade, andspaced means connected to the upper and lower extremities, respectively,of the first-mentioned blade for attaching it to an associated outboardmotor.

2. A weed cutter device, according to claim 1, wherein thelast-mentioned means comprise a link pivoted to the lower end of thefirst-mentioned blade, and a clamp having a pin and slot connection tothe upper end of the first-mentioned blade to accommodate verticaladjustment thereof with respect to the clamp, said clamp being formedand arranged to embrace an associated drive shaft housing.

3. A weed cutting attachment for outboard motors which comprises avertically disposed central cutting blade member, a pair of encirclingclamp elements for anchoring the upper end of said blade member to anoutboard motor vertical shaft housing, a pair of link straps forsecuring the lower end of the blade member to the shaft housing, a pairof formed sheet metal brackets 'of symmetric and opposite contour havingportions bolted to said central cutting blade member, each bracketincluding a sidewardly offset and rearwardly extending arm containing alongitudinal slot therein, and a pair of side cutter blade memberscomprising vertical knife blade portions disposed parallelly to saidcentral cutting blade member and having inwardly bent portions adaptedto be adjustably secured in the longitudinal slots of said brackets.

References Cited in the file of this patent UNITED STATES PATENTS NumberName Date 1,553,182 Mould Sept. 8, 1925 2,054,374 Fuller Sept. 15, 19362,140,099 Wise Dec. 13, 1938 2,319,640 Sink May 18, 1943 2,355,842 AradoAug. 15, 1944 2,468,890 Moore May 3, 1949 2,470,874 Sidney May 24, 1949

